Justin Trudeau kicked off a Liberal caucus retreat Wednesday insisting his government won’t back down on a plan to end tax provisions that it maintains give some wealthy small business owners an unfair advantage.

The prime minister’s opening message to caucus pre-empted Liberal backbenchers who’ve come to the retreat poised to press for changes to the tax plan after being inundated with complaints over the summer.

“People who make $50,000 a year should not pay higher taxes than people who make $250,000 a year.”

While he signalled a willingness to adjust the proposed tax changes, Trudeau was adamant that they won’t simply be abandoned in the face of a mounting backlash from doctors, lawyers, tax professionals, shopkeepers and others who’ve incorporated their small businesses to reduce their income tax bill.

“We are always open to better ways to fix that problem, but we are going to fix that problem,” he said.

One change would restrict the ability of incorporated business owners to lower their tax rate by sprinkling income to family members in lower tax brackets, even if those family members do no work for the business. Another would limit the use of private corporations to make passive investments in things like stocks or real estate.